Electrolytic reductions

Aminophenols are either made by reduction of nitrophenols or by substitution. Reduction is accompHshed with iron or hydrogen in the presence of a catalyst. Catalytic reduction is the method of choice for the production of 2- and 4-aminophenol (see Amines BY reduction). Electrolytic reduction is also under industrial consideration and substitution reactions provide the major source of 3-aminophenol. 

Reduction, electrolytic, 5, g3 Removal of CO from a-liydroxy acid,... 

Sources/Uses. Occur as emissions from coke ovens, from coking of coal tar pitch, and ftom Soderberg aluminum reduction electrolytic cells used for base coatings and paints for roofing and paving and as a binder for carbon electrodes... 

T0843 University of Cincinnati Department of Civil and Environmental Engineering, Reductive Electrolytic Dechlorination... 

The basic requirement of the redox oxidant in contact with n-type semiconductors is that it has an equilibrium potential more negative than the decomposition potential of the semiconductor and more positive than the lower edge of the semiconductor conduction band. The basic requirement of the reductant electrolyte is that its redox equilibrium potential be negative of the oxidant electrolyte and more positive than the lower edge of the semiconductor conduction band. More work will be necessary at characterizing solid electro-lyte/semiconductor interfaces with those solid electrolytes available before satisfactory solid-state devices capable of photocharge can be realized. 

Fig. 16 UV-Vis spectral changes for (OVPc (SC5Hn)8), observed using controlled potential electrolysis at potentials for the first reduction. Electrolyte = DCM containing 0.1 M TBABF4. Electrolysis time was 30 min. Reproduced with permission from [30]...

Fig. 10. Comparison of the catalysts/platinum, (2), and (86) for the Oj-reduction. Electrolyte 4.5 n HjS04...

Process Desulphurisation Pb02 reduction Electrolyte type Concentration Current (g/1) density Pb Free (A/m ) acid Pb02 preventing agent Anode Notes... 

Fe4S4(SR)4] , are good catalysts for reduction of CO2. Recently it was found that other compounds also facilitate such reduction. Electrolytic reduction of CO2 in acetonitrile in the presence of [Rh(dppe)2]Cl leads to the formation of The rhenium(I) compound [ReCl(CO)3 (bipy)] catalyzes electrolytic reduction of CO2 to carbon monoxide. The electrolytic reduction of CO2 in some cases probably proceeds via the radical anion C02 its formation explains various reduction products see scheme (13.241). Palladium complexes, for instance, [Pd2Cl2(dppm)2], [Pd(dppm)2], and [PdCl2(dppm)], slowly catalyze reduction of CO2 to methane, ethyl formate, and traces of ethyl oxalate. 

Tafel-type reduction Electrolyte Current density Required amount of B Current efficiency Sensitivity of B to oxidation Effect on B of variation in E Mode of cell operation Operational time of factory... 

Aromatic nitro compounds can be reduced in several ways, either to nitroso compoimds only, or up to amines. The usual color tests can then be carried out with the products or the reduction. Electrolytic reduction or reduction with zinc in CaCl2 solution leads to nitroso compoimds which can be detected by the reaction with sodium pentacyanoammoferroate (25) reduction with zinc in glacial acetic acid or in NH4CI, as well as reduction with stannous chloride, give rise to primary aromatic amines which can be detected either with /7-dimethylaminobenzaldehyde, or, after diazotization, by coupling with a suitable passive component (p. 341). 

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